Bench test setting. Configuration was set in the following order: 1. APAP device, 2. 180 cm SlimLine tubing, 3. Whisper Swivel II exhalation port, 4. connector, 5. Unintentional air leak (UAL) valve, 6. Starling resistance, 7. connector, and 8. ASL 5000 simulator. APAP = automatic positive airway pressure.